The purpose of this project is to characterize the catalytic center of glyceraldehyde 3-phosphate dehydrogenase using EPR spectroscopy. These studies will be correlated with the more detailed crystallographic analyses of other laboratories. The data on the structure and catalytic mechanism will be extrapolated to the functioning of the enzyme in both normal and dystrophic muscle. The observations on the abnormalities in dystrophic muscle may be useful in elucidating the etiology of the disease or in the design of therapeutic programs.